An equipment chassis is a structure that provides both mechanical support and electrical interconnections for electrical and electronic apparatus. For telecommunications applications, in particular, such equipment chassis are often designed as cabinets or racks for receiving and interconnecting various equipment, such as power supplies and electrical distribution devices. In the vernacular of the telecommunications industry, "cabinet" generally describes an enclosed rack-mount structure and "rack" generally describes an open-frame rack-mount structure; as used herein, "cabinet" and "rack" are used interchangeably to describe any structure for receiving and interconnecting electrical and electronic devices or systems, whether such structure is substantially "open" or "enclosed."
It is preferable that equipment cabinets incorporate a modular design philosophy that ensures easy access, simple installation, and fast maintenance and which allows a system to expand in capacity and hardware features as system needs change. Equipment cabinets are widely used in the telecommunications industry because telecommunications networks must be maintained in constant operation and modular equipment cabinets allow for the rapid replacement of failed devices.
In the telecommunications industry, in particular, equipment cabinets should allow for custom configurations and a relatively high density of installed components. A modular design of both the equipment cabinet and the equipment modules provides a customer with the ability to easily select the equipment modules necessary for a specific application. To minimize the number of cabinets required for an application, however, modularity should not come at the expense of decreased component density; e.g., a customer should not have to purchase additional equipment cabinets in order to house the necessary modules for a specific application. This is particularly true in the telecommunications industry where physical space is often limited, for example, within equipment huts at cellular antenna sites.
Prior art equipment cabinets and equipment modules, although providing for some modularity and some adaptability, have had limitations. For example, to accommodate different types of equipment modules or components--such as rectifiers, inverters, converters, system controllers, and AC and DC distribution and circuit protection elements--some equipment cabinets have included separate sections for different types of modules and components. In some cases, a cabinet section may only accept modules of the type designed for that section; thus, although there may be available space in one section of a cabinet, a second cabinet may be required if modules designed for a full section are incompatible with the mechanical and electrical accommodations in the cabinet section having available space.
As noted previously, an equipment cabinet should incorporate a design philosophy that ensures easy access, simple installation, and fast maintenance. During installation, some equipment modules, such as AC and DC power distribution modules, must have electrical conductors coupled thereto; the electrical conductors must also be decoupled when removing a module for replacement or repair. Whereas an equipment cabinet may have many electrical conductors routed to, from and between modules, it is preferable not only that there be easy physical access to each conductor and the coupling means on each module, but also that the conductors not be occluded by the modules or cabinet structure. Many existing equipment cabinets fail to provide such physical access to, and visibility of, the electrical conductors routed therein.